CVE-2020-10932

medium

Description

An issue was discovered in Arm Mbed TLS before 2.16.6 and 2.7.x before 2.7.15. An attacker that can get precise enough side-channel measurements can recover the long-term ECDSA private key by (1) reconstructing the projective coordinate of the result of scalar multiplication by exploiting side channels in the conversion to affine coordinates; (2) using an attack described by Naccache, Smart, and Stern in 2003 to recover a few bits of the ephemeral scalar from those projective coordinates via several measurements; and (3) using a lattice attack to get from there to the long-term ECDSA private key used for the signatures. Typically an attacker would have sufficient access when attacking an SGX enclave and controlling the untrusted OS.

References

Details

Source: Mitre, NVD

Published: 2020-04-15

Updated: 2024-11-21

Risk Information

CVSS v2

Base Score: 1.9

Vector: CVSS2#AV:L/AC:M/Au:N/C:P/I:N/A:N

Severity: Low

CVSS v3

Base Score: 4.7

Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Severity: Medium

EPSS

EPSS: 0.00033